Polyethylene terephthalate (PET) containers have been widely used as beverage bottles and containers for cosmetics, medicines, detergents, shampoos, and so on because of high transparency, gas barrier properties, and the like.
Although food packaging containers are rarely left outdoors for a long time and therefore not required to have high weatherability, they are usually kept on the grocery or supermarket shelves under sunlight or fluorescent lights and are required to have weatherability enough to keep the product's appeal to consumers.
Among known methods of light stabilizing various synthetic resins is addition of additives, such as ultraviolet absorbers, phenol or phosphorus antioxidants, and hindered amine stabilizers. Triazine compounds are known as highly effective ultraviolet absorbers and are disclosed, for example, in JP-A-2000-238857, JP-A-2001-302926, JP-A-2003-192830, and JP-A-2003-261725.